Comparison between intraamniotic PGF2 alpha and vaginal PGE2 for second-trimester abortion

Area of Science:

• Obstetrics and Gynecology
• Reproductive Medicine
• Pharmacology

Background:

• Second-trimester abortion methods require careful consideration of efficacy, safety, and patient factors.
• Prostaglandins are commonly used agents for inducing abortion.

Purpose of the Study:

• To compare the efficacy and safety of intraamniotic prostaglandin F2 alpha (PGF2 alpha) versus vaginal prostaglandin E2 (PGE2) for second-trimester abortion.
• To evaluate induction-to-abortion intervals, complication rates, and cost-effectiveness.

Main Methods:

• A comparative study of 203 consecutive patients undergoing second-trimester abortion.
• Administration of either intraamniotic PGF2 alpha or vaginal PGE2.
• Monitoring of induction-to-abortion (I-A) interval, abortion completion, side effects, and costs.

Main Results:

• Vaginal PGE2 demonstrated a significantly shorter average I-A interval (13.25 hours) compared to intraamniotic PGF2 alpha (18.53 hours), particularly in primigravidas.
• While abortion completion rates were similar (~50%), PGE2 achieved 97.6% completion within 24 hours versus 78.5% for PGF2 alpha.
• PGE2 required higher total doses and costs (2.8x greater) and was associated with more frequent side effects (vomiting, diarrhea, pyrexia, hypotension).
• Hypertension was more common with PGF2 alpha.

Conclusions:

• Vaginal PGE2 is a more effective agent for achieving timely second-trimester abortion, especially before 16 weeks gestation, due to its shorter I-A interval.
• The choice between PGE2 and PGF2 alpha should balance the benefits of a shorter I-A interval with PGE2 against its increased cost and side effect profile.
• For pregnancies under 16 weeks, vaginal PGE2 is recommended due to easier administration and faster results compared to PGF2 alpha, avoiding difficult amniocentesis.